The present disclosure relates to healthcare and medication delivery systems. In particular, the present disclosure relates to testing and controlling the quality of medical fluids being delivered to a patient using healthcare/medication delivery systems.
Complex medical fluids are often administered to a patient through a variety of different medication delivery systems. For example, a medication delivery system, such as a dialysis machine for performing peritoneal dialysis for a patient that may be experiencing decreased or total loss of kidney function, uses a dialysis solution to remove waste products from the bloodstream. In another example, a medication delivery system, such as an infusion pump, delivers a liquid drug or medical fluid such as morphine or the like to a patient based upon parameters entered into the medication delivery system. The medical fluid may be a homogenous liquid, a mixed solution, or a solution that includes particulates in a buffer liquid. The presence of the medication, or the correct concentration of the medication, in the solution being delivered to a patient is important to prevent medical errors. An error could include the administration of the wrong drug or an improper dose of the correct drug.
A problem associated with peritoneal dialysis, for example, is an improperly mixed solution delivered to a patient. The medical fluid, or dialysate, for peritoneal dialysis can be packaged in a dual-chamber bag, in which one chamber includes a buffer solution and the other chamber includes a concentrated glucose solution. The chambers of the bag are separated by a peel seal that is ruptured upon pressure exerted on one of the chambers. The pH value for both the buffer solution and the glucose solution, or pharmaceutical substance, are potentially harmful to the patient, but the resulting pH value of a completely mixed fluid containing both the buffer and glucose solutions is physiologically compatible. Accordingly, the failure of the peel seal to rupture completely may result in a mixed medical fluid containing an undesirable proportion of buffer solution to glucose solution. It is therefore desirable to test the medical fluid being transferred from the dual chamber bag to the medication delivery system prior to the medical fluid being delivered to the patient.
Several testing mechanisms exist for identifying pharmaceutical substances within a medical fluid and the concentration of such substances. Some testing mechanisms are integrated within the medication delivery system as permanent components. These integrated testing mechanisms are typically invasive. That is, the sensors used to detect various aspects of the medical fluid are in direct contact with the medical fluid. Between uses, these medication delivery systems are typically cleaned or sterilized. However, without proper cleaning or sterilization, the invasive testing mechanisms may contaminate subsequent medical fluids and patients.
Non-invasive testing mechanisms are also used for identifying pharmaceutical substances within a medical fluid and the concentration of such substances. The non-invasive sensors do not contact the medical fluid directly. Non-invasive testing mechanisms are typically less accurate than the invasive testing mechanisms due in part to the geometry and material of the barrier between the medical fluid and the sensors of the non-invasive testing mechanism.
A need accordingly exists for a sterile testing mechanism to test the for the presence or concentration, or both, of pharmaceutical substances in medical fluids to be administered to a patient. A need also exists for an inexpensive, single-use testing mechanism. Yet another need exists for an accurate testing mechanism for testing the presence or concentration, or both, of pharmaceutical substances in medical fluids to be administered. A need further exists for a method and apparatus for controlling the distribution of pharmaceutical substances in medical fluids once the presence or concentration of the substance in the medical fluid has been measured.